Trying to conceive? Avoid rotational shifts, heavy lifting

09 February, 2017

Working at night or on rotating shifts may also lead to decreased fertility.

Researchers analyzed nearly 500 women who sought infertility treatment at Massachusetts General Hospital from 2004 to 2015. The data was analyzed in order to see if there is a connection between these factors and infertility.

In addition, the women who reported working night or evening shifts had 24 percent fewer mature eggs, compared with the women who reported working day shifts only.

As for the non-day shifts, the study reveals that this occupational requirement is even more risky for the production of egg and the quality of the released eggs, compared with other women with a normal working schedule, at the same age and weight.

"You need a study in the thousands", he told CNN, also citing the need to consider differences including socioeconomic status and testosterone levels in the women.

Researchers tested the women's ovarian reserve - the number of remaining eggs - and their levels of follicle stimulating hormone (FSH).

When it comes to working night shifts or rotating shifts, the researchers mentioned that fertility can be affected because of the circadian rhythm disruption.

The researchers found that women with physically demanding jobs had a lower reserve of eggs than those whose work did not require regular heavy lifting.

The women gave details about their hours of work, their shift patterns and how physically demanding they found their schedule. This way they can increase their fertility.

The study showed that women who lift heavy object have 9% fewer eggs and 14% fewer mature eggs than women who don't have physically demanding jobs.

They also examined how many eggs were "mature" and capable of developing into a healthy embryo.

Published in the journal Occupational and Environmental Medicine, the findings were most prevalent in women who were overweight or obese, or over the age of 37 years old.

"It is hard to hypothesise a mechanism by which a physically demanding job may have a negative effect on ovarian reserve, as the number of eggs (oocytes) is determined at birth and lost progressively throughout life, with smoking having been shown to be the main toxin that significantly diminishes ovarian reserve".

It is the first study of its kind to measure whether workplace factors might affect a woman's biological capacity to have a baby.

And among women going through IVF, those with physically demanding jobs had a lower total reserve of eggs and fewer mature eggs.